Thermal and photochemical stability of poly(vinyl alcohol)/modified lignin blends
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Data
2006-05-01
Autores
Fernandes, D. M.
Hechenleitner, AAW
Job, A. E.
Radovanocic, E.
Pineda, EAG
Título da Revista
ISSN da Revista
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Editor
Elsevier B.V.
Resumo
A kraft lignin derivative (KLD) obtained by reaction with p-aminobenzoic acid/phthalic anhydride was blended with poly(vinyl alcohol) (PVA) by solution casting from DMSO. PVA and PVA/KLD films were exposed to ultraviolet radiation (24, 48, and 96 h) and analyzed by thermogravimetry (TG), differential scanning calorimetry (DSC), infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance (H-1 NMR) spectroscopy, and scanning electron microscopy (SEM). PVA films show a loss of thermal stability due to irradiation. PVA/KLD reveals greater thermal stability than PVA and an increase in thermal stability after irradiation. These results suggest that the incorporation of KLD into PVA provides a gain in thermal and photochemical stability. FTIR, H-1 NMR, DSC, and TG results obtained for the blends suggest that intermolecular interactions between PVA and KLD chains are present. SEM micrographs revealed blend miscibility for a KLD blend content of up to 15 wt%, as observed at magnification of 1000 times. (c) 2005 Elsevier Ltd. All rights reserved.
Descrição
Palavras-chave
kraft lignin derivative, poly(vinyl alcohol), blends, NMR, FTIR, SEM
Como citar
Polymer Degradation and Stability. Oxford: Elsevier B.V., v. 91, n. 5, p. 1192-1201, 2006.